/*
 * Copyright (c) 2011, Michael Bedward
 * 
 * All rights reserved.
 * 
 * Redistribution and use in source and binary forms, with or without 
 * modification, are permitted provided that the following conditions are met:
 * 
 * Redistributions of source code must retain the above copyright notice, this 
 * list of conditions and the following disclaimer.
 * 
 * Redistributions in binary form must reproduce the above copyright notice, 
 * this list of conditions and the following disclaimer in the documentation 
 * and/or other materials provided with the distribution.
 * 
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" 
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE 
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 
 * POSSIBILITY OF SUCH DAMAGE.
 */

package com.mousebender.gridfacade;

import com.vividsolutions.jts.geom.Coordinate;
import com.vividsolutions.jts.geom.Geometry;
import com.vividsolutions.jts.geom.GeometryFactory;

import com.mousebender.gridfacade.jts.RectCoordinateSequence;

/**
 *
 * @author michael
 */
public class GridViewCell {
    
    private static final GeometryFactory GF = new GeometryFactory();
    
    /**
     * Location outside grid view bounds.
     */
    public static final GridViewCell NOWHERE = new GridViewCell(Double.NaN, Double.NaN, 0, 0);
    
    /**
     * Tests if a cell is equal to {@linkplain #NOWHERE}.
     * 
     * @param cell the cell to test
     * @return {@code true} if equal to {@linkplain #NOWHERE}
     * @throws IllegalArgumentException if {@code cell} is {@code null}
     */
    public static boolean isNowhere(GridViewCell cell) {
        if (cell != null) {
            return Double.isNaN(cell.cornerCoord.x) && Double.isNaN(cell.cornerCoord.y);
        }
        
        throw new IllegalArgumentException("coord must not be null");
    }
    
    
    private final Coordinate cornerCoord;
    private final double xdim;
    private final double ydim;

    public GridViewCell(double minX, double minY, double xdim, double ydim) {
        this.cornerCoord = new Coordinate(minX, minY);
        this.xdim = xdim;
        this.ydim = ydim;
    }

    public Coordinate getCornerCoordinate() {
        return new Coordinate(cornerCoord);
    }
    
    public Coordinate getCentreCoordinate() {
        return new Coordinate(cornerCoord.x + xdim / 2, cornerCoord.y + ydim / 2);
    }

    public boolean isNowhere() {
        return GridViewCell.isNowhere(this);
    }
    
    public Geometry toGeometry() {
        RectCoordinateSequence coordSeq = new RectCoordinateSequence(
                cornerCoord.x, cornerCoord.y, xdim, ydim);
        
        return GF.createPolygon(GF.createLinearRing(coordSeq), null);
    }
    
}
